The International Residential Code (IRC) specifies a minimum 4/12 pitch (4 inches of vertical rise for every 12 inches of horizontal run) for a clay or concrete tile roof, except that a pitch as low as 2-1/2/12 is allowed when two layers of underlayment are applied.

    Florida Building Code (FBC) specifies that clay and concrete tile be installed to the standards in the Florida Roofing and Sheet Metal Association’s (FRSA) Concrete and Clay Roof Tile Installation Manual FRSA/TRI 07320. The manual lists different minimum slopes according to the type of underlayment and tile installation method, which varies from 2/12 to 4/12. It is also an excellent contractor resource, with extensive illustrations of flashing and other installation details.

• • • • • • • • • • • • • • • • • • • • • • • • • • • •  

  To learn more about roofs and attics, see these other blog posts:

• Why is my roof sheathing sagging between the trusses?

• Why is granule loss a problem for an asphalt shingle roof? 

• What are the mistakes to avoid when doing attic improvements?

• What causes roof shingles to curl up at corners?  

• What causes shingles to buckle along a line on the roof?

• What causes leaks at a fake roof dormer? 

• What causes a sagging roof ridge line?

• What causes bubble-like blisters in a built-up and gravel roof?  

• Why does it cost so much more to replace a steep roof than a low slope roof? 

• What is "ponding" on a flat roof?

• Is an attic required to have a light by the building code? 

• How can I inspect my roof for hurricane damage?

• Why is premature curl of roof shingles a problem?

• How can I tell if a roof has more than one layer of shingles? 

• What are the common problems with attic insulation? 

• What is the life expectancy of an asbestos cement shingle roof? 

• What's the average lifespan of a roof?

• Why is it a mistake to replace a roof and not replace its flashings? 

• Why is there no attic access hatch in the house?

• What is the building code requirement for an attic access hatch, scuttle, or door? 

• Does a roof with multiple layers of shingles last longer?

• What can I do to prevent roof leaks?

• Are roof trusses better than roof rafters (stick framing)? 

• Why is a popped nail in a shingle roof a problem? How do I fix it?

• What are the most common problems with wood roof trusses?

• What causes a lump or dip in the roof? 

• If my roof is not leaking, why does it need to be replaced?

• How can I be sure my roofing contractor got a permit?

• How many layers of roofing are allowed on a home? 

• What does "lack of tab adhesion" in an asphalt shingle roof mean?

• Why do roof edges start leaking?

• Why do my dormer windows leak? 

• Do home inspectors go on the roof? Do they get in the attic?

• Should I put gutters on the house? 

• How much of a roof truss can I cut out to make a storage platform in the attic? 

• What's the difference between an "architectural" and a regular shingle roof? 

• Why does my homeowner's insurance want a roof inspection?

• What are the hazards to avoid when going into an attic? 

     Visit our ROOF AND ATTIC page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.